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| =How to Create a PDMS-Stamp from Silicone/Araldite Mold=
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| Why PDMS? -> [http://en.wikipedia.org/wiki/Polydimethylsiloxane PDMS] is optically clear (good for microscopy!), and, in general, inert, non-toxic, and non-flammable.
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| ==Preparation of PDMS mixture==
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| * with pipette boy and 5ml stripette pour ~4g of elastomer into a (clean) cup
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| * with micropipette (1000µl) add one tenth of elastomer mass (~0.4g) of linker fluid to the cup
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| * mix well with stripette
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| * degass for 30min-60min
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| ==Preparation of PDMS membrane==
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| * pour degassed mixture onto wafer placed in petri dish with aluminium foil
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| * pour just enough to cover the waver
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| * use [[Christian Niederauer/Notebook/RacingBacteria/Stock/Leveling_Petri_Dish | Leveling Petri Dish]] to ensure constant thickness
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| * araldite wafer: cure it for 3-4 hours in oven at 60°C
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| * silicon wafer: cure it for 2 hours in oven at 80°C for
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| * peel off membrane from wafer surface with forceps
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| * cut out the pattern but '''leave enough space around it'''
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| ==Final Processing==
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| * punch holes with 2mm coring tool at the desired connection points under dissection microscope (tip: target the hole with coring tool under microscope, then put the stamp onto one finger with alufoil between stamp and finger and push/turn until you feel the coring tool on your skin)
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| * [[Christian Niederauer/Notebook/RacingBacteria/Protocols/Plasma_Cleaning | plasma clean]] the treated face of the stamp and a coverslip and press them together with alufoil in order to prevent contamination
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| ===If the stamp is too thin===
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| '''BEFORE PUNCHING HOLES'''
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| * take a slice of PDMS with bigger or same area than the stamp
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| * [[Christian Niederauer/Notebook/RacingBacteria/Protocols/Plasma_Cleaning | plasma clean]] unshaped face of stamp and extra slice and stick them together
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| * now punch desired holes with 2mm coring tool
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| ===How to clean the PDMS cup===
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| * scratch out all solid PDMS residues with forceps
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| * use tissue to clean out crudely
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| * pour pentane into the cup and gently sway the cup
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| * clean out with water and let dry
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| ===How to clean dirty stamp===
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| * let the stamp soak in ethanol
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| * use forceps and (with caution) submerge the stamp into a jet of water
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| * let dry on clean alufoil
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